How AFM Works
Atomic force microscopy is arguably the most versatile and powerful microscopy technology for studying samples at nanoscale. It is versatile because an atomic force microscope can not only image in three-dimensional topography, but it also provides various types of surface measurements to the needs of scientists and engineers. It is powerful because an AFM can generate images at atomic resolution with angstrom scale resolution height information, with minimum sample preparation.
So, how does an AFM work? In this page, we introduce you to the principles of an AFM with an easy to understand video animations. Feel free to share this page with others, and to email us if you have any questions.
'Nano', from the Greek word for 'dwarf', corresponds to a prefix denoting a factor of 10-9. Thus, a nanometer is one billionth of a meter, which is the length scale at which intermolecular force and quantum effect take hold. To put the nanoscale in a more understandable perspective, consider that the size of an atom relative to an apple is similar to the size of an apple relative to the planet Earth! Atomic Force Microscopes (AFMs) give us a window into this nanoscale world.
- Surface Sensing
An AFM uses a cantilever with a very sharp tip to scan over a sample surface. As the tip approaches the surface, the close-range, attractive force between the surface and the tip cause the cantilever to deflect towards the surface. However, as the cantilever is brought even closer to the surface, such that the tip makes contact with it, increasingly repulsive force takes over and causes the cantilever to deflect away from the surface.
- Detection Method
A laser beam is used to detect cantilever deflections towards or away from the surface. By reflecting an incident beam off the flat top of the cantilever, any cantilever deflection will cause slight changes in the direction of the reflected beam. A position-sensitive photo diode (PSPD) can be used to track these changes. Thus, if an AFM tip passes over a raised surface feature, the resulting cantilever deflection (and the subsequent change in direction of reflected beam) is recorded by the PSPD.
An AFM images the topography of a sample surface by scanning the cantilever over a region of interest. The raised and lowered features on the sample surface influence the deflection of the cantilever, which is monitored by the PSPD. By using a feedback loop to control the height of the tip above the surface—thus maintaining constant laser position—the AFM can generate an accurate topographic map of the surface features.
Applications of AFM
Finding new materials with innovative characteristics at the nanoscale have helped guide the development of many industries in the modern age. Such materials have been behind breakthroughs in sectors such as energy, transportation, and life science.
To investigate and characterize innovative nanomaterials, scientists choose Park AFM. Our technical know-how and deep knowledge of various applications helps researchers find a way to examine their samples with unmatched accuracy and productivity.
Characterizing electrical, magnetic, mechanical, and morphological properties of materials are possible with the dedicated operating modes available with Park AFM. With this versatility, our customers can upscale their research capabilities and continue kindling the spirit of innovation and progress brought about by breakthrough nanoscale investigations.
Cross-section of Polymer Film
Cross-section of Polymer Film Imaging a Narrow Area Using a Park AFM Instrument. Case Study : Cross-section of a Polymer Film
Production and Measurement of Nanodot Aarry
Production and measurement of Nanodot Array Methods of Exploiting Anodic Aluminum Oxide and Block Copoolymer as Templates on method of producing nanostructures is by using nanoscale templates.
Polymer Composite (Phase Separate)
Polyer Composite (Phase Separation) Easy to Detect Phase Information for composite Materials by Force Modulation Mode.
Phase Separate in the Co-Extruded Polymer
Phase Separation in the Co-Extruded Polymer Instability Flow in the Multi-Layered Copolymer Force Modulation Microscopy (FMM) is one of the unique AFM modes that is gaining more popularity.
Green Chemical Polymer
Green Chemical Polyer Water-Soluble Polymers are Developed for Environmentally Friendly Polyer Coating Applications.
Nano Materials Applications
Ultimate Resolution of AFM in Air
"What is the ultimate resolution of AFM in air?" This is a very important question because we all want to know the size of the smallest detail on our samples an ambient AFM can show.
Park SMartScan and AutoScript : Improving Operational Throughput and User Productivity
Ultra-High Resolution Atomic Force Microscopy
The goal of all forms of microscopy is to enable the observation of increasingly small objects and their details and characteristics which cannot be seen without aid.
Fast Imaging Using Park NX10 Atomic Force Microscopy
True Sample Topography Acquired by Low-Noise Z Position Sensor
True Sample Topography Acquired by Low-Noise Z Position Sensor True Sample Topography Acquire by Low-Noise Z Position Sensor Ahram Kim
SrTiO3 Surfaces by Using Park Systems AFM
Zinc Oxide Surfaces
Zinc Oxide Surface nanoscale AFM and KPFM Mapping of Localized Charge and Recombination center on chemically active ZnO surfaces case study.
AIGaN/GaN HEMT Reliability
ALGaN/GaN HEMT Reliability Park AFM Instruments create new ways to understand GaN HEMT reliability issues.
Patterned Array of Magnetic Nanostructures
Nanoparticles / Nanotubes
Nanoparticles / Nanotubes mechanical properties (F-D Spectroscopy) FD spectroscopy of the Ag particle show aberrations associated with the indentation of the nano-particle.
Graphene (Step Height)
Graphene (Step Height) Metrology - (True-NC-AFM, Contact AFm and STM) Graphene is a sheet of carbon atoms bound together with double electron bonds only one atom thick.
Graphene Membrane / Graphite
Graphene Membrane / Graphite mechnical properties - nanoindentation graphite is a layered compound composed of carbon atoms.
Thin Film - ZnO
ZnO Electrical Property (EFM/SKPM) The material and electrical properties of Zinc Oxide (ZnO) have made the compound attractive in the area of thin film transistors and light emitting diodes.
Characterization of Epitaxially Grown MnAs Films Using AFM and MFM
Characterization of Epitaxially grown MnAs Films Using AFM and MFM introduction and sample description because of its ferromagentic properties with well-orientated interfaces at room temperature.
Surface Morphology of Electrospun Fibers
Surface Morphology of electrospun fibers investigation of phase morphology for E-spun fibers composed of Polybutadiene and Polycarbonates.
Textile Nanocharacterization : Topography, Phase Imaging, and Nanomechanical Property Investigation of Polyester Yarn.
The addition of nanotechnology to textile development can yield next-generation fabrics for many new exciting applications.
Collagen Fibrils Imaging in Air and in Liquid using atomic force microscope-based fast nanomechanical mode
Collagen is a protein that provides structure in various connective tissues in animals and can be found in ligaments, tendons, and skin.
Nanoscale surface photovoltage
Nanoscale surface photovoltage spectroscopy investigation of nanostructures utilizing the Park AFM instruments case study.
Atomic Force Microscopy and Raman Spectroscopy
Atomic force microscopy and raman spectroscopy (AFM/Raman).
Quantum Dots / Photonic Devices
Quantum Dots / Photonic Devices Optical Properties - SERS / NSOM / Topography - gold nanoparticles are imaged with high resolution.
Electrical & Electronics
For many, the electronics industry has been a cornerstone in bringing about the prosperity of the modern age. Electronics have completely transformed nearly every facet of day-to-day life, stoking a nearly insatiable societal and economic demand to continuously improve our devices. One of the chief ways to do so is for device companies to produce faster, smaller, cheaper, and more power efficient portable devices. However, the critical dimensions of these products have to be engineered on the order of nanometers. Characterizing electrical properties at nanometer-size, such as electrostatic force interactions, surface charges, conductivity, and electrostatic capacitance directly determines the product quality and performance in each device. Yet, such characterization something that cannot be easily done at an industrial scale with existing tools.
Enter Atomic Force Microscopy (AFM). AFM's high nanoscale resolution and high sensitivity can fulfill the highly challenging requirements of nanoscale electrical property characterization. Park AFM provides industial-quality electrical property detection tools with high productivity to our customers in both research and industry.
- How to obtain sample potential data for SKPM measurement
- Scanning capacitance microscopy characterization of Vacuum-Channel Nanoelectronic devices
- Electrical characterization of Semiconductor device using SCM and SKPM Imaging
- Fully Automated Atomic Force Microscopy Measurement and Analysis Using Park NX System
- Accurate dopate profile of semiconductor device structure with QuickStep scanning capacitance microscopy
- Etched silicon structures
- Critical dimension measurement of high aspect ratio trench with park AFM
- Atomic force microscopy investigation of 1D structures utilizing the park AFM instrument
- Surface Topography Considerations of Patterned Sapphire Substrates for Blue/Green Light emitting diode
Solar Cell Applications
- Solar cells
- Characterization of Organic Photovoltaic cells
Semiconductor-based device fabrication and microelectromechanical systems (MEMS) technology have been major sources of the great success enjoyed by the modern high-tech manufacturing industry. Semiconductor-based device fabrication produces logic and vertical memory devices (fin structure, STI, TSV), liquid crystal displays (LCD), light-emitting diodes (LED), organic LED (OLED), and contact image sensors (CIS), etc. MEMS structures provide various photonic applications including the production of wave guide structures. In those industrial device manufacturing processes utilizing both semiconductor-based and MEMS techniques, reviewing (inspection) the correct dimension of device structures and any unintended defects on on them is critical to maximize productivity and cost-efficiency at every step of the whole in-line process.
Recently, as the size of both device structure and defect becomes smaller, down to the range that optical inspection techniques are unable to detect, the need to review at higher and higher sensitivity has been increasing in the manufacturing industries. This has resulted in the adoption of techniques capable of nanometer resolution review such as atomic force microscopy (AFM).
Many industrial researchers and engineers choose Park Automated AFM for their review of aspects of structural geometry such as feature height, pitch, critical dimension (CD), angle, and even sidewalls together with roughness analyses. This is due to their awareness of Park Automated AFM's accurate measurement results, low system noise, high-throughput rate, and minimized tip-to-tip variation from True Non-Contact™ mode AFM imaging technology.
- Wafer defects can't hide from Park Systems
- Studying Post-etching silicon crystal defects on 300mm wafer by automated defect review AFM
- Automatic defect review AFM with enhanced vision
- Sub-Angstrom roughness repeat-ability with tip-to-tip correlation
- Automated AFM significantly boosts throughput in automatic defect review
- Automated defect review (ADR) of 300mm Bar Wafer with automated AFM
- High throughput and non-destructive sideway roughness measurement using 3-dimensional AFM
- New 3D-AFM for high resolution sidewall imaging
- Chemical mechanical polishing (CMP) metrology with advanced AFM surface profiler.
- New 3-Dimensional AFM for CD Measurement and Sidewall Characterization
Life science has a direct connection in improving the quality of life for all of humanity. Advances in this domain have innumerable applications in the health, pharamaceutical, and agricultural industries. As time marches on, we are pressed by new challenges to better understand the phenomena of life not yet illuminated by the light of science. One such daunting frontier is at the nanoscale. Applying atomic force microscopy (AFM) to life science, researchers are now allowed to begin exploring the darkened mysteries at this border with the unknown.
Researchers using Park AFM in life science can acquire the nanoscale morphology of biological samples accurately and easily. Of particular use is the the force-distance spectroscopy that AFM provides. This technique allows for the characterization of biological materials along such physical properties as stiffness, adhesion, and even its Young's modulus with sub-nN level precision.
Furthermore, Park AFM has developed an innovative in-liquid imaging technology, Scanning Ion Conductance Microscopy (SICM). This technique has enabled researchers to study complicated physiological phenomena in liquid directly, something not possible with conventional microscopes. Not only are physiological biomaterials and live cells able to be imaged with Park SICM, but various pipette-based applications can be integrated into the investigation such as patch clamping for ion channel signal detection, electrochemical reaction analyses, and even nanoinjections or nanobiopsies.
Cell Biology Applications
- Park PinPoint Mode for Cell Biology
- Live Cell Volume Measurement of SICM
- SICM Image of Suspended Collagen Fibrils
- Embryonic Stem Cell
- Mouse Sperm Cells
- Human Astrocytoma Cells
- AFM and Confocal Fluorescence Microscopy can be Complementary Tools
Micro and Molecular Biology Applications
- Imaging of Plasmids in Liquid using True Non-Contact Mode Atomic Force Microscopy
- True Non-Contact Imaging of Various Samples
- Hair Damage From Sunlight Radiation Characterization Using Atomic Force Microscopy
- Collagen Fibrils Imaging Using Park NX10 Atomic Force Microscope PinPoint Nanomechanical Mode
- Cellulose Nanowhiskers Topography & Young's Modulus Imaging Using Atomic Force Microscopy
- Single Strand DNA Molecules
- DNA Oligonucleotides
- Liposomes and Vesicles
- Lipid Vesicles and Bilayer
- Targeted Patch Clamping with Scanning Ion Conductance Microscopy
Nanotechnology is one of the latest research fields that rely on manipulation of matter on an atomic and molecular scale. Innovation resulting from nanostructure breakthroughs have brought numerous technological advances in both research and industry, contributing to the progress of other research fields as well. These days, using nanostructure fabrication methods in various ways has become standard research in improving product performance irrespective of industry.
To fabricate and characterize nanoscale structures, researchers have been utilizing AFM to find practical solutions since the development of the first commercial AFM from Park Systems. Park Systems’ advanced AFM know-how and a self-developed and especially accurate feedback control system in their AFM products allow their customers to both image and manipulate nano-structures with increased accuracy and with higher productivity.
Nano Fabrication Applications
- High Aspect Ratio Structure
Nano Lithography Applications
- Thin Film Nanolithography (XEL)